Water-craft



Patented Mal'. 29, 1921.

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. 1. HAFSTROM. WATER CRAFT.

APPLICATION FILED APR. I7, 1918.

W. I. HAFSTROM.

WATER CRAFT.

APPLICATION FILED APII; I?, 191ey menamar. 29, w21.

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W. J. HFSTROM.

WATER CRAFT.

APPLICATION man APH. 17, 1918.

Eatented Mar. 29, 192B.

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d?. (MM @ijf Y@ the WILLIAM J. HAFSTROIVI, OF CHCAGO, ILLINIS.

WATER-CRAFT.

Leraars.

Specieation of Letters Patent.

Patented Mar. 29, 19921..

Application filed April 17, 1918. Serial No. 229,004.

T 0 all whom it may concern.

Be it known that 1, 1XWILLIAM J. HAF- s'rROM, a citizen of the UnitedStates, and a resident of Chicago, in the county of Cook and State ofillinois, have invented certain new and useful improvements in Water-Craft, of which the following is a specification.

My invention relates to water craft, particularly to that class whichwhen in motion is sustained partly by flotation on water and partly bythe air. Y

The broad object of my invention is to produce a water craft which canbe driven at high speed by water engaging propulsion mechanism and thensustained in great part by suitable wings or vanes so that the craft cantravel in a more horizontal line irrespective of the waves or brokenwater surfaces.

More in detail, one important object of the invention is to providepropulsion mechanism in the form'of hollow spiral propel- 1ers which inaddition to acting as oats and water engaging propellers, act also asairl engaging propellers when raised above the water. Another feature ofthe invention is to provide vanes or wings suitably secured to andextending from the craft body for sustaining a great part of the vehicleload when it vis rapidly traveling in order that the craft, when inrapid progress, will hit only the high spots of the water, so to speak,suitable rudder mechanism being provided for determining the directionof travel of the craft and for causing the desired elevation of thesustaining planes with reference to the horizontal.

The above and other features of my invention are clearly disclosed onthe accompanying drawing in which- Figure 1 is a'plan View,

Fig. 2 is a side elevational view,

Fig. 3 is a rear elevational view,

Fig. 4 is a sectional view on plane Ll-h Fig. 1, and

Eig. 5 is a sectional view on plane 5 5, Fig. 1.

The supporting frame F of the craft is in the form of a boat andconstructed of sheet metal or other material and in such manner as to bestrong and light. rPhe prow 10 is shaped and curved so as to out downthe resistance when inthe water. Extending laterally from the front ofthe boat body are the brackets or arms 11 and 12 and at the rear of theboat similar arms or brackets 13 and 1d extend laterally. These armsafford bearing support for the hollow spiral propeller structures P andP. Each propeller structure comprises a hollow shaft section 15surrounded by the hollow worm or thread 16, these parts being of sheetmetal so that the propeller structures will be strong and light and willserve as floats. rlhe ends 17 and 18 of the propeller shafts arepreferably conical so as to reduce the resistance when the craft istraveling through the water or in the air. The ends of the shaft of thepropeller P have bearing in the ends of the arms 11 and 13, while thepropeller P has bearing support in the ends of the arms 12 and 14, thepropellers being parallel with the craft body. rPhe worm or threadarrangement may be single or multiple and the pitch such that the craftcan be given great speed when the propellers are :rapidly rotated.

Extending from the crests of the propeller worms or threads and suitablyspaced, are the fins or vanes 19 whose pitch is the same as that of thethreads. The arrangement of the vanes on each propeller is such thattheir engagement with the water will assist the threads or worms inrapidly propelling the craft, and by their engagement with the air thesevanes act together like the ordinary propellers of aeroplanes.

Describing now the driving mechanism for the propellers, a suitableengine E is mounted in the craft body E, the engine shaft 2O beingournaled at its outer end in the bearing structure or frame 21.Journaled in this frame structure and in the end wall 22 of the craftbody are the transmission shafts 23 and 24 carrying outside of the wall22 the intermeshing gears 25 and 26. The pinion 27 on the engine shaftmeshes with the pinion 28 on the transmission shaft 23 so that when theengine shaft is driven the gears 25 and 26 will be rotated. The outerends of the shafts 23 and 24 also support sprocket wheels 29 and 30which are connected by chains 31 and 32 with the sprocket wheels 33 and311 secured to the propeller' structures P and P just within the arms 13and 111, the rotation of the gears 25 and 26 being thus transmitted tothe propellers. 1With the arrangement shown the propellers are rotatedin opposite directions, but the screws or worms are so arranged that thepropellers will cause propulsion of the sides of the craft body F arethe planes or wings 35 and 36, these wings being rectangular andpreferably parallel with the propeller axes. Suitable anchor or tie rods37 and 38 connect the outer corners of the wings with the ends of thecraft body and keep the wings in proper alinement. At

their innerends the wings are preferably curved to parallel thecircumferences of the propellers, as clearly shown in Fig. 4.

R represents a rudder structure which comprises the horizontal steeringplane 39 and the vertical steering plane 40 extending downwardly fromthe center line of the hori- Zontal plane. The rudder structure ispivoted at the apex of the V-frame 41 as indicated at p, which at theends of its limbs is pivoted to the lugs 42 and 43 extending rearwardlyfrom the arms 13 and 14, the frame 41 with the rudder structure pivotedthereto being therefore capable of being swung Vvertically and therudder structure being capable of Vswinging horizontally at the pivot p.Atthe front end of the craft body the operating mechanism O for therudder structure is situated. The tubular shaft 44 is suitably journaledand carries a drum 45 for the cable ends 46 and 47 which extend aroundguide pulleys 48 and 49 and fasten at their outer ends 50 and 51 to therudder plane 39 so that turning of the hand wheel 52 secured to theshaft 44 will cause horizontal swing of the rudder around-the pivot p.Extending through the tubular shaft 44 is the shaft 53 which supportsthe drum 54 for the cable ends 55 and 56, the cable end 55 passing overthe guide member 57 and being secured at its end 58 to the outer end ofthe rudder structure at the top thereof. The cable end 56 travels aroundsuitable guides 59 and 60 and is secured at 61 to the rear end of therudder plane 40 a distance below the top thereof. With this arrangementturning of the shaft 53 by the hand wheel 62 causes the rudder structuretogether with its supporting frame 41 to swing vertically around'thecenter of the pivot connections 42 and 43.

When the craft is at rest its boat body F and the hollow propellerstructures will support its weight, the dimensions being preferably suchthat the propeller structures will be only partly immersed in the water.When the engine is operating and connected, the propeller structureswill be rapidly rotated and the lins 19 coperating with the worms willcause the craft to acquire great speed through the water. y of the nsand Vworms with the water will The engagement Y have a tendency to raisethe craft with reference to the water in. proportion as the speedincreases, and thus the resistance is reduced. When the vehicle isundery headway the wings or planes 35 and 36 will cooperate with the airto prevent sudden dropping of the craft where the water surface isbroken or wavy. By adjusting the rudder structure the craft can betilted so as to bring the sustaining planes at an angle with thehorizontal, the planes then exerting raising effort on the craft andtakin up'the greater part of the load. The cra is thus practicallycarried bodily by the sustaining planes across the crests Vof the wavesor broken water surface and can travel inV a straight line withouthaving to follow the irregular water surface. Although the fins 19 ofthemselves are not able to propel the craft sufficiently to permit thesustaining planes to hold the craft entirely above the water, yet theirengagement with the air Y adds greatly to their propulsion effect andthat of the worms in the water.

rl`he craft is more vor less self-controlling during travel. If thetilted sustaining planes tend to carry the craft too far out of thewater the engagement of the' worms and fins for water propulsion willdecrease and the speed of the craft retarded to permit it to settlesuiiiciently in the water to increase the water propulsion area. Y

As the inner ends of the sustaining planes curve around the propellerstructures pockets are formed into and through which the propellersrapidly draw the air so that the sustaining effort of the planes isincreased and steadied. Y

I thus provide a very simple yet highly veflicient water craft whichcanbe propelled at great speed through and along the Vsurface of a bodyof water and whose forward travel is along a straight line irrespectiveof waves or broken water surfaces. Y

l do not of course desire to be limited to the precise shown anddescribed as changes and modifications are no doubt possible which wouldstill comewithin the scope of the invention. I claim as follows: Y

1. A water craft comprisingV a body provided with planes'extendinglaterally therefrom, a buoyant propeller mounted beneath said body andprovidedv with a deep helical groove extending longitudinally thereofand a plurality of blades-mounted onsai propeller'intermediate saidgrooves. l Y

2. A water craftV comprising a body, a buoyant propeller mounted beneath:said body and having a ldeep helical groove extending longitudinallythereof, a plurality of radially extending blades mounted yon saidpropeller, and a horizontal rudder prostructure and arrangement surfaceof the water. f

3. A Water craft Icomprising a body, buoyand having deep helical groovesextending ant propellers mounted beneath said body longitudinallythereof, and blades arranged and having deep helical grooves extendinghelically intermediate said grooves, and a longitudinally thereof, andblades arranged combined horizontal elevator and vertical 5 helicallyintermediate said grooves, a horirudder mounted on said body, andelevator 15 zontal elevator mounted on said body, and and ruddercontrolling mechanism. means for elevating and depressing said ele- InWitness whereof, I hereunto subscribe vator. my name this 12th day ofApril, A. D. 1918.

4. A Water craft comprising a body, buoyl0 ant propellers mountedbeneath said body WLLIAM J. i STROM.

